Considered Unmarried
To qualify for head of household status, you must be either unmarried or considered unmarried on the last day of the year. You are considered unmarried on the last day of the tax year if you meet all the following tests.
You file a separate return (defined earlier under Joint Return After Separate Returns ).
You paid more than half the cost of keeping up your home for the tax year.
Your spouse did not live in your home during the last 6 months of the tax year. Your spouse is considered to live in your home even if he or she is temporarily absent due to special circumstances. See Temporary absences , later.
Your home was the main home of your child, stepchild, or foster child for more than half the year. (See Home of qualifying person , later, for rules applying to a child's birth, death, or temporary absence during the year.)
You must be able to claim an exemption for the child. However, you meet this test if you cannot claim the exemption only because the noncustodial parent can claim the child using the rules described later in Children of divorced or separated parents or parents who live apart under Qualifying Child or in Support Test for Children of Divorced or Separated Parents or Parents Who Live Apart under Qualifying Relative. The general rules for claiming an exemption for a dependent are explained later under Exemptions for Dependents .